Artificial leather products used in a vehicle interior material, furniture for home and office, shoes, and the like have been manufactured while the finished products still contain a large amount of various volatile organic compounds (VOCs). In fact, an artificial leather fabric, for example, PVC (Polyvinyl chloride), Polyurethane (PU), and Thermo Polyurethane (TPU), is used as a base material for the artificial leather products and treated with various chemicals during the manufacturing process.
The organic compounds which are generated during the manufacturing process of the artificial leather are classified into a very-volatile organic compound (V-VOC), a volatile organic compound (VOC), and a semi-volatile organic compound (S-VOC) based on a boiling point thereof. The very-volatile organic compound (V-VOC) refers to a compound that has a low boiling point and naturally volatilizes and disappears and thus rarely has a bad influence on the human body. The semi-volatile organic compound (S-VOC) volatilizes at very high temperature of 240° C. or higher and thus rarely has a bad influence on the human body in daily life.
However, the volatile organic compound (VOC) has a bad influence on a user's body, for example, by causing various diseases and headache. In order to remove such a volatile organic compound (VOC), an adsorbent is sprayed and coated on the manufactured artificial leather fabrics and a reaction is performed for adsorption at a certain temperature range, thereby removing the volatile organic compound contained in the artificial leather and the odor caused by the volatile organic compound.
In one example of spraying, a method of manufacturing a chemically adsorbed film formed in a monomolecular film has been reported. The method includes: a process of spraying a solution containing a chlorosilane-based adsorbent having a molecule containing a straight carbon bond or a straight siloxane bond with a chlorosilyl group on its one end to react with a surface of a substrate; a washing process of removing the solution containing the chlorosilane-based adsorbent, which is not reacted with the substrate and remains on the substrate, by using a nonaqueous organic solvent; and a process of reacting the remaining chlorosilyl group with water.
In other example of coating, a method of manufacturing a chemical adsorption film has been reported. The method includes: reacting a chemical adsorbent with a surface of a base material containing an active hydrogen group; washing and removing a solution containing the unreacted adsorbent remaining on the base material by using an organic solvent; reacting the base material with water; and drying the resultant product to manufacture a chemical adsorbent film formed in a covalently bonded monomolecular film.
However, in such techniques described above, the volatile organic compound is immobilized or chemically bonded to the adsorbent. Indeed, the volatile organic compound cannot be actually removed, and does not volatile even under the conditions for volatilization.
Thus, in conventional methods, even if a volatile organic compound (VOC) is treated with an adsorbent or the like, the volatile organic compound is immobilized or chemically bonded to the adsorbent and remains on the surface of the artificial leather. Therefore, when the volatile organic compound is exposed under severe conditions, for example, high temperature in daily life, volatilization of the volatile organic compound may occur. As a result, the surrounding air may be contaminated and other damages may be caused by the volatile organic compounds.
In particular, if the volatile organic compound is used in a vehicle interior material, and since a vehicle is air-tightened and is frequently exposed to sunlight or a high-temperature weather condition, volatilization of the volatile organic compound occur. Therefore, the problem is more serious.
Accordingly, standards and regulations on odor and volatile organic compounds (VOCs) have been strengthened. However, the conventional method of adsorbing a volatile organic compound (VOC) including spraying and reacting an adsorbent hardly satisfies the required standards. Therefore, the vehicle users have complained about serious problems after use for a considerable time. In general, even after a certain period of use, the users have not yet satisfied because of odor.
Therefore, a method for removing a noxious odor substance containing a volatile organic compound (VOC) from the artificial leather has been urgently needed.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.